Sartre is one example of someone who does just this. Every text is, after all, a human document and whatever Kierkegaard thought about God was clearly a matter of human thought that can, in principle, be retrieved and interpreted by other human beings. A phenomenological approach to religion must, it seems to me, adopt the old adage: nothing human is alien to me.

Religious life is about something real in human experience that is not constrained by what Wittgenstein called 'all that is the case'. In this sense Heidegger is not simply 'mistaken' - he just asks us, as philosophers mostly do, to think more carefully about what we're saying.

And one thing the void certainly can teach us is how to wait, how to become truly patient, and how to let go of superfluous intellectual baggage - all of which is a good lesson for hyper-agitated multi-tasking goal-focussed contemporary human beings.

Of course, if one's reading Kierkegaard for personal interest that's fine - but it's sloppy scholarship just to cherry pick what suits one from a particular author, whether it's Kierkegaard, Heidegger, or whoever. Nevertheless, it does seem to me that even the more religious parts of the authorship can offer significant insights into the meaning of the human condition to those who can't then say that, e.g., they believe Jesus Christ is the Son of God and their personal Saviour.

It seems that just Being, the sheer fact of existence, that there is something rather than nothing, already inspires a wonder akin to religion. But - as in my comment about the Kingdom of God in the last answer - Jewish and Christian traditions are also prepared to challenge what 'is' for the sake of what could be.

Of course, it's always difficult to disentangle fact from fiction in relation to, e.g., the singularity project. Many scientists I know are dismissive of transhumanist claims, BUT the last 100 years has surely taught us never to underestimate the pace and scope of scientific progress. However, even if much of this turns out to be science-fiction, it also reveals a way of thinking about human life that I find deeply troubling.

And this is also what he takes Christian doctrine, in all its complexity, to be centrally about, that is, teaching an attitude rather than a set of propositions. Call it joyous openness to life. What's not relevant about that?